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Hack ShowcaseThe spotlight of some of our favourite hacks. Consider this our Seal of Quality™.

Relive the adventure of the second generation Pokemon games in a more challenging and complete way!

Hack of: Pokemon Crystal

Features

Very exhaustive work on the selection of wild Pokemon including fishing, headbutt, rock smash and all types of event Pokemon, and trainer parties including every single trainer in the game as well as around 100 additional trainers carefully distributed throughout the adventure. Similar work on choosing the items found, sold in marts, or obtained in any different way, as well as on adjusting their prices.

Plenty of mechanical changes that contribute to the difficulty increase, such as the progressive level increase of wild and trainer Pokemon, the inhability to use healing items whilst in battle, a forced "set" battle style, developments regarding the experience mechanics, a trainer EV system, the removal of badge boosts, improved AI, and more.

Extensive work on the balancing of learnsets (without altering the movepools), evolution levels, base experience, growth rates, catch rates, held items and other aspects inherent to the Pokemon, adequated to the usefulness and strength of each Pokemon species and other characteristics of the game.

Enjoy additional events and other existing events that have been modified, explore new places and plenty of remodeled maps like caves and several routes, and fight lots of additional trainers distributed in caves, routes, gyms, or in the new events. Most of these features are located in Kanto to extend and make more enjoyable the second part of the adventure. Speaking of Kanto, now you can enjoy the Kanto journey following the order of the first generation games!

Screenshots

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AI: Improved the AI of the lesser trainer classes as well as a few other aspects of the AI. The 25% added chance of missing with a status or stat reduction move by the opponent has been removed.

BADGE BOOSTS: Stat and type boosts provided by badges removed in order to give the game a more "professional" feel and increase the difficulty by removing an unfair advantage.

BASE EXPERIENCE: Adequated to the stats of each Pokemon (proportional to the base stat total of each Pokemon).

BASE MONEY: Adequated to each trainer class, and to how early can it be found for the first time and in general.

BATTLE STYLE: Battle style option removed; it's SET by default.

BERRY TREES: A few different berry trees, and two berries found per tree instead of one!

BERSERK GENE: Berserk Gene is no longer removed permanently once used, similarly to what occurs with other in-battle effect items such as Quick Claw and Leftovers. However, it's temporarily removed for as long as the current battle lasts, meaning that it will only activate once per battle.

BUG CATCHING CONTEST: The formula that determines the points obtained has been adjusted according to the changes in Pokemon and levels.

CATCH RATES: Adequated to how common and useful each Pokemon is.

CATCH RATE FORMULA: Four minor bugs in the catch rate formula of the original Pokemon Crystal have been fixed.

EXPERIENCE GAIN: The changes in the experience mechanics have been mainly applied to encourage training a full team of Pokemon over training just one or two Pokemon. The experience formula has been modified to make the experience gain increase by multiplying the original experience with the result of player's Pokemon level / enemy's level (*). The other main change consists on a badge-sensitive experience cap, that prevents your Pokemon from growing up past certain levels depending on the amount of badges collected.

EVOLUTIONS: Changes on evolution levels, adequated to the strength of the evolution chain and to the level at which the Pokemon appears for the first time. For a few Pokemon, different methods in which they evolve. Trade evolutions have been replaced. **

FLEEING POKEMON: Some different species of Pokemon that can flee.

GROWTH RATES: The growth rate of each species of Pokemon has been adequated to the general usefulness of the evolution chain the Pokemon belongs to. Every Medium Slow growth rate has been replaced.

GYMS: The player is unable to leave a Gym until he or she beats the Gym Leader or all his/her Pokemon faint in battle (blackout). Thus, Gym trainers and the Leader have to be beaten in succession. Gym Leaders all have 6 Pokemon, so do members of the Johto League.

HEALING ITEMS: Properities of healing items (potions, berries...) edited so that said items can't be used in the middle of a battle. However, no changes in the functions of the items when held by a Pokemon (berries still heal, boosting items still boost a type etc.). Trainers no longer will use healing items themselves either.

HELD ITEMS: Different wild held item data and increased probability of appearing the second item. More emphasis on generic items but rarer or unique items like Leftovers, Scope Lens and type boosting items can also be found.

ITEMS: Different items found in the floor, and different hidden items. Some differences in items sold in marts as well as in other events such as the Game Corner, Lucky Number, Bug Catching Contest or Buena's Show. As usual, lower profile items are found earlier while higher profile items are found as the game progresses, but more emphasis on more useful and obscure items. Different item prices (or coins @ Game Corner), adequated to the utility and accessibility of each item.

LEAGUE REMATCH: Rematch a stronger version of the Johto League after completing the Kanto adventure!

LEARNSETS: Minor changes on learnsets like level modifications or twists and, to a lesser extent, egg moves or RBY/GSC TM moves made level up moves as long as legally possible. In any case, move compatibilities and illegal combinations are left unchanged. **

MONEY LOST: Money lost upon losing a battle is no longer halved, as the money lost depends on the highest leveled Pokemon in the player's party, following the formula [ Level * (No. Badges + 4) * 10 ].

MOVE TUTOR: A new unique move tutor found in Johto that can teach your Pokemon a variety of R/B/Y TM moves, always accounting for illegal move combinations.

OBEDIENCE: The obedience will never be a factor due to the experience gain capping at a certain level (see EXPERIENCE GAIN) before the obedience level is reached.

POKEMON: Modified wild, fishing, headbutt, rock smash, trainer, and event Pokemon species and levels as well as amount of Pokemon used by trainers and their movesets. Logic prevails on wild encounters. Pokedex completion is possible.

SHINY POKEMON: Different DV requeriments and increased probability (1/256) for a Pokemon to be shiny. The properities of the shiny Gyarados and Odd Egg Pokemon have been adequated accordingly. In addition, new shiny Pokemon colors.

TEXT: All the corresponding text edits to make everything coherent to the changes applied in Pokemon, mechanics and events.

THIEF: Thief has no effect unless it's used in a wild battle (no wild Pokemon knows Thief), or in a link battle.

TIME OF DAY: Morning, day and night times delayed two hours (06-11 morn | 12-19 day | 20-05 nite).

TRAINER DVs: Different trainer DVs (usually higher), mostly adequated to how early a trainer of that class can be found. DVs of many classes are maximized.

TRAINER EVs: A Trainer EV System that provide trainer's Pokemon a gradual and controlled boost of their stats according to their levels to simulate boosts provided by EVs.

TRAINER HOUSE: The Trainer House event (in Viridian City) now includes battles that become more difficult progresively and the player will receive a prize after a win.

X ITEMS: The use of "X Items" (besides X Accuracy) such as X Attack and X Defend limited to one at the same time (in other words, these items are not stackable).

**: Since the gradual level increase inevitably makes the player's Pokemon grow much faster, a general delay on evolution levels and learnsets has been applied in order to prevent the player from obtaining fully evolved Pokemon or powerful moves early on (which, subsequently, would imply the need of making early trainers have, similarly, overevolved Pokemon or overpowered moves to make the game competitve enough). Every learnset and evolution level has been modified accordingly, and the availability of some TMs has been delayed as well.
(*): The effect will only take place if the opponent's level is the highest of the two, meaning that a high leveled Pokemon will not get disfavored. In addition, this factor caps at 2/1 to prevent ridiculous experience gains.

Bug fixes (Updated 20/9/2015)

Unlimited berries

Kadabra not evolving into Alakazam

Traded Pokemon possibly not obeying at high levels

Possibly getting stuck in Viridian Gym

Losing to Blaine and still getting the badge

Cooltrainer inside Victory Road challenging multiple times

Moltres not disappearing immediately after being fought

Names of some Elite Four members being incorrect

Cleanse Tag and Mystic Water properties (game crashing when depositing the former in the PC)

Some trainers in Rock Tunnel or in Vermillion Gym acting as "already fought" if found before beating Misty

Cinnabar gym statues freezing the game if talked to before defeating Blaine

Very nice, I'm just starting off right now, and it already has a different presence.

Is there a list of changed evolutions? I was wondering mostly for trade evolutions, as they're usually the most varied amongst hacks. If not, could I cop a hint for them? Just in the general method of their evolution?

All the trade evolutions have been replaced with either level evolutions (most cases) or stone evolutions. I don't want to give a list of the exact evolution levels and that, because I'd rather people find it for themselves, which I believe can be more exciting. In general, the evoltion levels have been slightly delayed for the reasons I stated in the main post.